 So, let's move to radiofrequency ablation with Dr. Krokidis in small primary endophyte greener tumors. Thank you. Thank you, Mr. Chairman. I do thank the organizing committee. I'm delighted to be here and be part of the kidney cancer association. So, I'm going to argue in favor of the use of RFA in hyalur endophyte greener tumors. I would quickly introduce the treatments that you all know about. It's a very well known, the fact that Refrectum was introduced by Robson in the 70s and then evolved in laparoscopic techniques, robotic, we've seen, minimally invasive. And then laparoscopic ablation was introduced with use of thermal techniques in aim for nephron-sparing treatments, and this evolved percutaneous image guide ablation. However, if we think that we deserve the idea of treating tumors with ablation, we have to look at the history of medicine and think about Hippocrates and his statement 400 years before Christ that whatever cannot be excised can be chewed by a coterie or burned. And he was definitely ahead of his times. However, we don't really know what he meant by coterie. Was he really that ahead? Was he thinking of heat or ice? And was he thinking of the modern device that we have and the dilemmas that appear in the modern practice? Well, if we think about RF, we have to look at the technique and how is this technology evolving the tumor. It is based on the use of radiofrequency waves that oscillate the ions of the tissue and this ionic agitation cause frictional heat and this motion energy is becoming thermal energy and it cooks the tissue. This is a very precise and repetitive cooking and it's very effective. It was introduced nearly 20 years ago in clinical practice in an interoperative setting by a Belgian group and then the first percutaneous case was done 1998 at the Massachusetts General Hospital. Since then a lot of series were published with fantastic results for small renal tumors with nearly 100% success rate in long term results. If we see the cancer survival score, we see that for up to three years we have very good results that excess 90% in multiple studies. So this is an established treatment for small renal tumors. Also for single kidneys, we have seen in our experience with Gaisens and Thomas, that after 56 months of mean follow up, the results were very good in terms of oncology control. The setting for RFA is very simple. We need a scanner, this is a scanner at Adam Brooks and we need a generator which is located here. The patient is usually anesthetized by local anesthesia or conscious sedation. He's positioned prone in the scanner. We need the monitor to identify where our needles are and if you see these pictures this is an enhancing lesion, it's a typical RCC in terms of imaging, and then after calibrating and positioning the needle in the exact middle of the tumor, ablation is performed and as you may see there's no enhancement in the tumor and that indicates treatment. And that's how tumors look three years after being ablated. There's a scar on this picture that shows that there's no enhancement and this is a very good result. If you have problems in terms of other organs like in this case the bowel is dangerously near the tumor, also in the prone position where the patient is positioned for his treatment and in this case would like to displace the bowel and we do that with a little bit of dextrose, 5%, which is non-ionic solution and radiofrequency ablation is not transmitted and therefore we can ablate safely the lesion. Thermal ablation in our recent published meta-analysis has shown to be very effective. It's, we have now long-term data, we don't have any randomized controlled trials but from the existing trials we can see that this is a technique that it is comparable to surgical techniques nowadays. Well, if we go back to Hippocrates, is that all? Is that, is RFA perfect then? Well, we have to think about central lesions. What's going on with central lesions and this is the argument of today's debate. So if we think about the location of lesions within the kidney, the upper part we can say that it's clear RFA territory. We can ablate every lesion up to four centimeters of course. With a lower line, it's definitely an area where most of the radioses would see it as a very dangerous area to treat. However, experts in the field have stated in the past that RFA is not influenced by the position and the location of the lesion. It has to be performed safely. And this trial has shown that in 41 patients, 41 tumors in 39 patients with endophytic location, ablation was performed safely with very good results at approximately three years. But how can we ablate the central lesion? Well, we have to protect the pelvic-alysel system the way we protect the bowel. And in this case, we have to position it at an extent and perform cooling of the pelvic-alysel system with the use of dextrose, which is perfused from the urethra extent. And in this case, central lesion, which is located here, which can be considered as a challenging case with the use of a urethra extent and perfusion of the pelvic-alysel system. We can ablate, this is our needle, that is in the center of the lesion and we can perform a safe ablation of this small renal tumor without damaging the pelvic-alysel system. In a similar case, in a more central location, the urethra extended position, payload perfusion, and our needle is positioned here and a very good result at one year. So RFA is feasible for central lesions. But this is better than cryo. Well, cryo, we've seen that it's based on a different principle. It's based on formation of ice. It's more controlled. We can see it with imaging modalities. Ice is usually performed extracellularly and the cells are killed by dehydration. And then intracellular ice is performed and coagulation accrosses due to thrombosis of small vessels. The cryo ablation has been for a long time in the urological field. However, the first pyrtutanus case was performed in 2001 and this is the publication. And as you may see, this is the ice ball and this is how pictures of cryo ablation look. Since then, a lot of debate was on what would be the ideal ablation technique and a lot of publications were appeared. And in 2008, this meta-analysis has compared the two modalities in a very large number of patients. It's actually 1,375 patients. And patients were coming from a lot of institutions. Cryo ablation was performed mostly intra-operatively, whereas radiofrequency ablation was performed percutaneously. And there was no true difference between the two modalities. So from the data that we have until now, the two methods are completely comparable. Also, in a more recent publication, 2012, regarding renal function, in a sense with already impaired renal function, we have seen that there's no difference of the EGFR at one month at one year post-ablation of both modalities. We need also to consider that cryotherapy is a little bit more demanding in terms of technical aspects. This is the setting. And it's definitely time consuming to organize. It's definitely demanding terms of technical knowledge and money. It's definitely more expensive than radiofrequency ablation. And it's not without complications. Well, we need to think that we have to position multiple needles, and there's risk of bleeding. There's no track ablation, so there's risk of seeding. The cost is definitely significant, as mentioned. It's time consuming, and it requires significant expertise. And there's also always a risk of thermal injury with the skin. So if we have to compare between the two modalities, we have to say that even though cryo is the new thing, the number of probes, the multiple number of probes, the significant technical effort and cost, and the fact that we cannot ablate the track make this modality less appealing. Whereas RFA has established results the last 10 years for small renal tumors, it is feasible for central lesions. And the cost is low, and the technical effort is also not significant for an experienced operator. So if we go back to the hypothesis, we can say that he would say today that RFA is feasible for central lesions. RFA is effective for small renal tumors. RFA is cheaper than cryo ablation, and RFA is more straightforward than cryo. So probably he would suggest that we could treat every lesion with RFA if it's smaller than four centimeters. We can reserve cryo and multiple probes for large lesions. We have to use RFA if we want to be cost effective, and if we want to treat challenging cases that cannot be treated in another way, then probably cryo is the best solution. Thank you very much.